With pastures withered from a lingering drought, farmers in Texas and northwest Louisiana have abandoned donkeys by the hundreds, turning them into wandering refugees that have severely tested animal rescue groups.

The nation's biggest donkey rescue group says that since March 2011, it has taken in nearly 800 donkeys abandoned in Texas, where ranchers mainly used the animals to guard their herds. Many of the cattle and goats have been sold off, largely because of the drought and the nation's economic slump, putting the donkeys out of a job.

And although the drought that began in late 2010 is over now, the flood of donkeys continues, said Mark Meyers, executive director of Peaceful Valley Donkey Rescue.

"Last week I spent two days on the road and got 20 donkeys each day," he said Wednesday. Since then, he's had a call of about 12 more in the Midlands, Texas, area.

"Hay prices still haven't come down. And what little grass is growing, people are going to save it for the animals that are going to make them money," he said.

In the north Louisiana town of Athens, Keith Gantt, who rounds up loose livestock for the Claiborne Parish Sheriff's Office, says he has dozens of donkeys that he can't give away. Some he's had for two years.

"People just turn 'em out on the highway. The sheriff's department makes me go catch them and then I get stuck with them," he said.

The donkey market has shriveled with the dried-up fields of Texas, where auction houses won't take them.

"The last ones we tried to sell, they brought the donkeys back to us. They tried to get a $5 bid for both of them and couldn't get a $5 bid," Deputy Bill Pentecost, who wrangles stray livestock for the Williamson County Sheriff's Office north of Austin, said last month.

Texas has 1.4 million fewer cattle than it did a year ago, a drop of 10.5 percent.

"Texas has large, large, large, large ranches. As the wells dried up and grazing's gone down, animals are coming up to the fence to eat. People are realizing they've sold all their cattle ... but they've got 20 donkeys," Meyers said earlier this year.

His organization, the largest such group in the U.S., normally takes in about 400 donkeys and burros — small, feral donkeys — a year. Since March 2011, he said, the group has accepted nearly 800 donkeys abandoned in Texas — 600 last year, 172 so far this year. Some were abandoned, some abused and some caught in roundups of herds on federal lands.

The drought, the economy and the high price of hay have forced ranchers across the state to sell off their livestock. Meyers said he's been paying $290 to $350 a ton for hay, compared to a top price of $90 in normal times, and must send as far as Montana and Minnesota to get it. Even if the weather allows a crop this year, the price isn't likely to go down immediately, he said.

People often sneak donkeys onto somebody else's land, he said. "They'll drive a couple counties over, look for a place where there's a bad part on a fence and kick them onto somebody else's property. I get a call at least once a week from somebody saying, 'I woke up and found donkeys on my property.'"

Texas ranchers use female donkeys to guard remote herds of livestock, said Kathy Dean, CEO and founder of Longhopes Donkey Shelter in Bennett, Colo. They're docile, friendly, and don't eat like a horse, she said.

However, the animals are instinctively hostile to dogs and their cousins: wolves and coyotes. "They will bray, bare their teeth, run and chase, and attempt to bite and kick an intruder," according to a Colorado State University fact sheet. In 1989, it said, 1,000 to 1,800 of 11,000 Texas sheep and goat producers used guard donkeys.

While Peaceful Valley has about 1,850 rescued donkeys in Texas, California and Oklahoma, Longhopes has a total of about 40 at any one time. It's among a handful of donkey rescues around the country, Meyers said.

He said that out of the 772 Texas donkeys that Peaceful Valley has taken in, he's been able to place only about 40 with adoptive owners. One reason is that most were uncastrated males — about eight of those for every female he's rescued. Ranchers may keep females to guard their sheep, cattle or goats, but males are too aggressive, he said.

Donkeys' physiology makes them harder to castrate than horses, so the operation is more expensive.

Gantt, a Claiborne Parish livestock farmer who works on contract for the sheriff's office, blames U.S. Sen. Mary Landrieu, D-La., for the scores of donkeys he's taking care of. Landrieu was among sponsors of a measure that shut down the nation's only horsemeat processing plant by forbidding the U.S. Department of Agriculture to inspect such plants.

It wasn't renewed last year, after the Government Accountability Office reported that it seemed only to have moved the slaughter. About 100,000 horses a year had been killed at the last U.S. plant, and about that many were being shipped to Mexico and Canada for slaughter.

However, it doesn't appear that many donkeys were ever slaughtered. A Colorado State University study published in 2001 found that of 1,348 animals surveyed at the three horse slaughterhouses then open, four were donkeys or mules. If those proportions were typical, 100,000 slaughtered equines might include 300 donkeys and mules.

Given those numbers, "it stands to reason that other factors are responsible for the hundreds of abandoned donkeys," Landrieu spokeswoman Erin Donar said. Landrieu said she plans to push for a bill that would forbid both horse slaughterhouses and exportation of horses for slaughter.

Gantt contends that closing the slaughterhouses cut the base price for horses so low that there was even less market for donkeys.

Turning Pointe Donkey Rescue in Dansville, Mich., usually has about 20 to 25 animals at a time, said president Sharon Windsor. She said she was recently asked if she could take 44 from Texas.

The number was likely to increase because none of the jacks was castrated and "they're all running around together," she said. Nor was that the only problem. To be adoptable, donkeys must be friendly and trained.

"Some of these donkeys are wilder than a March hare," Windsor said.

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